Document and Entity Information - shares	3 Months Ended
	Dec. 31, 2019	Feb. 07, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--09-30
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	001-39030
Entity Registrant Name	CERENCE INC.
Entity Central Index Key	0001768267
Entity Incorporation State Country Code	DE
Entity Tax Identification Number	83-4719946
Entity Address Address Line1	15 Wayside Road
Entity Address City Or Town	Burlington
Entity Address State Or Province	MA
Entity Address Postal Zip Code	01803
City Area Code	857
Local Phone Number	362-7300
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	CRNC
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		36,438,513